Road-finishing machine



March 1s, 1952 H. R. HORNING 2,589,257

ROAD-FINISHING MACHINE Filed July l. 1948 6 Sheets-Sheet 1 mi M7#ATTORNEYS March 18, 1952 H. R. HoRNlNG ROAD-FINISHING MACHINE Filed Julyl, 1948 6 Sheets-Sheet 2 INVENTOR.

March 18, 1952 H. R'. HoRNlNG ROAD-FINISHING MACHINE 6 Sheets-Sheet 3Filed July l, 1948 JNVENTOR: Haro/0 l?. Harm/7g ,4 ATTORNEYS.

March 18, 1952 H. R. HORNING ROAD-FINISHING MACHINE Filed July l, 1948IN VEN TOR: Haro/d A? Hom/ng BY M 1,47 .L M ATTORNEYS March 18, 1952 H.R. HoRNlNG 2,589,257

ROAD-FINISHING MACHINE Filed July l, 1948 6 Sheets-Sheet 5 ATTORNEYSMarch 18, 1952 H. R. HORNING 2,589,257

ROAD-FINISHING/MACHINE Filed July l, 1948 6 Sheets-Sheet 6 Fi .14sINVENToR l5 Y Haro/d Ebb/'ding BY M, 'LM

ATTORNEYS Patented Mar. 18, 1952 ROAD-FINISHING MACHINE Harold R.Horning, Columbus, Ohio, assgnor to The Jaeger Machine Company,Columbus, Chio, a. corporation of Ohio Application July 1, 1948, SerialN0. 36,464

16 Claims. (Cl. 94-45) My invention relates to a road-finishing machine.It has to do, more particularly, with a nishing machine provided with ascreed structure having an associated oscillating cut-off and compactormember. The screed structure is designed for advancing into materialwhich is deposited on the surface to be covered, such as black-top orconcrete material, so as to cut- Voff such material, compact it, andlevel it to the desired thickness and crown to produce the nished layerof material.

This application is related to my co-pending application directed toRoad-Paving Machine, Serial No. 36,463, filed Jul;7 1, 1948.

One of the objects of my invention is to provide a road-finishingmachine with a screed structure of such design that as it advancesthrough the material, it will direct the material downwardly andrearwardly under the smoothing surface of the screed and will compact iteffectively as it is guided under such surface.

Another object of my invention is to provide a screed structure whichhas a cut-off and compactor bar at the forward side thereof whichengages the material, the bar being so shaped that it will effectivelyagitate the material as it advances thereinto and is being oscillatedbut will also guide the material rearwardly and downwardly and compactit during this guiding action, rather than merely agitate the materialand tend to force it forwardly, and will eventually cut it off at thelevel of the smoothing surface of the screed.

Still another object of my invention is to provide a screed structure ofthe type indicated having a cut-off bar and compactor with a serratededge for engaging the material, the serrated edge being disposed in axed angular position relative to the final smoothing surface of thescreed so as to guide the material downwardly and rearwardly beneathsuch surface.

A further object of my invention is to provide a screed structure of thetype indicated wherein the cut-off bar and compactor is supported forhorizontal oscillation relative to the final smoothing surface of thescreed so as to effectively agtate the material which its serrated edgeengages `and to compact it and guide it beneath such smoothing surface.

Another object of my invention is to provide a screed structure of thetype indicated above wherein 'both the serrated cut-olf and compactorbar and the finishing surface can be adjusted 2 readily to provide fordifferent crowns without interfering with the bar oscillating means.

An additional object of my invention is to provide a screed structure ofthe type indicated wherein the cut-off bar and compactor is supportedfrom the screed structure for oscillation by means including bearingstructures which permit the oscillation but require no lubrication.

An additional object of my invention is to provide a screed structure ofthe type indicated above having means associated therewith foreffectively heating the serrated cut-olf bar thereof and the nishingsurfaceA thereof so that the screed can effectively operate on black-topor similar material.

Another object of my invention is to provide a finishing machine havingflexible cushioning means for suspending a screed structure therefrom inworking position which means is adjustable readily to vary the amount ofweight applied by the screed structure to the material upon which it isacting.

Another object of my invention is to provide a finishing machine havingmeans for suspending the screed structure therefrom in such a mannerthat it can be quickly and easily raised to inoperative position fortransportation or lowered to operative position for acting upon thematerial.

Various other objects will be apparent from the drawings and thefollowing description.

In general, the finishing machine of my invention includes a screedstructure which will act on material deposited on the surface to becovered in front thereof and which is preferably associated with amaterial receiving and spreading unit. The latter unit may be of anysuitable type and the detailed structure thereof does not form apart ofthis invention. For example, it may be a tractor typeunit with conveyorsthereon for receiving' the material from a dump. truck at the front ofthe unit, which will convey the material rearwardly and deposit it infront of a driven spreading member supported by the unit and extendingtransversely of the surface, such member serving to spread the materialtransversely. The spread material will be acted upon by the screedstructure of my invention which is supported from the tractor unit atthe rear thereof and extends transversely of such unit. Y

The screed structure of my machine is suspended from the tractor unit bya cable arrangement which permits the entire structure to be loweredquickly into operative position relative to the surface to be covered orto be raised to inoperative position for transportation. When inoperative position, the screed structure is suspended at its ends by acable and pulley arrangement which has a cushioning unit incorporatedtherein that will provide for yieldable suspension of the screedstructure from the tractor. This cable and pulley arrangement isprovided with adjustable ratchet units at each end of the screedstructure whereby the resistance of such cushioning unit can be variedso that more or less of the weight of the screed structure will'besupported from the tractor unit and, therefore, the amount of weightacting on the material being nished can be varied. Themeans forsupporting the screed structure from the tractor unit includes pivoteddrag links which serve to drag the screed structure along with thetractor unit and which also serve to keep the screed structuresubstantially vertical preventing it from tipping forwardly orrearwardly. These links permit the necessary vertical movement of thescreed structure. The screed structure includes a forward verticallydisposed plate extending the full width thereof which serves to engagethe material as the machine advances and to protect the mechanism of thescreed structure from the material. The lower edge of this plate isinclined rearwardly and downwardly for deflecting the material under thescreed structure. Directly behind this inclined edge of the plate is thecutter bar and compactor which is provided with a serrated or toothedforward edge that is inclined rearwardly and downwardly to the sameextent as the lower edge of the material-engaging plate. Directly behindthe cutter bar is the surfacing member of the screed which embodies aflat horizontally disposed plate that is at the same level as theextreme lower edge of the serrated cutter bar and extends rearwardlytherefrom. Thus, the cutter bar is disposed between the front verticallydisposed material-engaging plate and the rear horizontally disposedsurfacing plate. The cutter bar is suspended from the main screedstructure by hanger links of the pendulum type which can swingtransversely and which are located behind the front plate that protectsthem from the material. These links are provided with novel pivots orbearings at each end which require no lubrication. Thus, the cutter baris supported for horizontal oscillation and it is oscillated by aneccentric mechanism which may be driven by a flexible power-take-offdrive from the tractor unit, such drive permitting the necessaryvertical movement of the screed structure. The surfacing plate issupported from the main screed structure by independently adjustablethrust rods which can be adjusted to bow it to the proper crown. Also,the cutter bar is made in several independent sections to permitrelative angular adjustment in accordance with the crown imparted to thesurfacing plate, this adjustment being accomplished by verticaladjustment of the pivot supports for the pendulum links which aredisposed at the ends of said sections. This adjustment can be madewithout interfering with the eccentric drive for oscillating the cutterbar. A heat conducting duct is associated with the surfacing plate andthe cutter bar for heating such members and a heating system is providedon the` machine for supplying heat to such duct. At the ends of thetransverse screed structure, side edging plates are provided which aresupported for free vertical movement or floating movement relative tothe screed structure and which serve to form straight edges on thefinished layer of material.

The preferred embodiment of my invention is illustrated in theaccompanying drawings wherein similar characters of reference designatecorresponding parts and wherein:

Figure 1 is a side elevational view of a roadnishing machine embodyingmy invention.

Figure 2 is a plan view of the machine of Figure 1.

Figure 3 is an end elevational view of the machine.

Figure 4 is a side elevational view of the machine illustrating thedriving mechanism and the screed-supportingV means thereof.

Figure 5 is a plan view of the machine with cover plates removed to showcertain mechanism thereof.

Figure 6 is a vertical sectional view through the screed structure,along line 6-6 of Figure 4 showing the means for suspending andoscillating the cut-off and compactor bar.

Figure 7 is a horizontal sectional View taken substantially along line'I-l of Figure 6.

Figure 8 is a horizontal sectional View through a cushioning unit usedin the yieldable suspension of the screed structure from the machine.

Figure 9 is an enlarged transverse section through the screed structuretaken substantially along line 9-9 of Figure -6.

Figure 10 is a perspective view of a section of the screed structure atthe lower side thereof illustrating the cutter bar and compactor and theassociated surfacing member of the screed.

Figure 11 is a diagrammatic view illustrating how the screed structurewill advance into the material and the oscillating cutter bar will guideit downwardly and rearwardly while compacting it until it is finallyunder the surfacing member of the screed.

Figure 12 is a perspective view, partly cut away, showing the ductarrangement for heating the cutter bar and surfacing member of thescreed structure.

Figure 13 is a diagram illustrating a heater connected to the ductarrangement of the screed structure.

Figure 14 is a section taken along line Ill- I4 of Figure 9 illustratingone of the cutter bar suspending links, and associatedparts.

With reference to the drawings, in Figures 1 to 3, inclusive, I haveillustrated generally a finishing machine in which my invention may beincorporated. The machine comprises a tractor unit I having a screedstructure 2 associated with the rear end thereof and extendingtransversely thereof. The tractor unit I may be of any suitable type butpreferably is of such a type that it will receive material from a dumptruck, carry it rearwardly and deposit it on the surface in front of thescreed structure 2. The unit I will travel on the surface to be coveredwhile the screed structure 2 will engage the surfacing material andproduce the desired nished surface thereon.

The tractor I includes the power-driven crawlers 3 and 4 which run onthe surface to be covered. It also includes the pair of conveyors 5 andE which extend from the front thereof to the rear thereof and which areadapted to receive the material andto conduct it rearwardlyl of thetractor where it is deposited on. the surface in front of the screedstructure. The material discharged from the conveyors 5 and 6 isdeposited in front of a rotatable spreading member, supported by tractorunit I at the rear thereof, which includes the sections 1 and 8 composedof helically arranged blades which serve to feed the materialtransversely in opposite directions. Thus, the sections 1 and 8 of thespreading member will spread the material across the surface before itis engaged by the screed structure 2.

As shown best in Figures 4 and 5, driving means is preferably providedon unit I for driving the crawlers 3 and 4 independently, for drivingthe conveyors 5 and B independently and for driving the sections 1 and 8of the spreader member independently. This driving mechanism includes amotor 9 which drives a transmission unit ID. The unit I drives atransverse shaft II by means of a chain drive I2 and also drives asleeve I3, rotatable on the shaft II, by means of a chain drive I4. Thesleeve I3 drives the crawler 4 through the medium of a sprocket I5carried thereby which is drivingly connected to the crawler 4 by meansof the chain I6, While the shaft I I drives the crawler 3 through asimilar chain drive including the sprocket I1 carried thereby.Associated with the sprocket I5 is a clutch I8 and associated with thesprocket I1 is a clutch I9 by means of which either of the crawlerdrives may be rendered operative or inoperative. The transmission I0also drives a short shaft 20 which drives a sprocket drive 2I that, inturn, drives a shaft 22 which extends almost completely across the unitI at the rear side thereof. This shaft 22 serves to drive varioussprocket and chain drives similar to the drive IB. These drives includesprockets 23 and 24, carried by the shaft 22 towards its ends, and apair of sprockets 25 and 26, carried substantially midway of the ends ofthe shaft. The sprocket 23 will drive the conveyor 6 and the sprocket 24will drive the conveyor 5. The middle sprocket 25 serves to drive thesection 8 of the spreading member while the adjacent sprocket 28 servesto drive the section 1 of the spreading member. Associated with thesprockets 23, 24, 25 and 26 are the clutches 21, 28, 29 and 30,respectively, by means of which any of the sprockets may be coupled toor uncoupled from the shaft 22. Thus. either section 6 or 1 of thespreader member can be actuated independently, or either of theconveyors 5 or 6 can be driven independently. The independentlycontrolled drives for the crawlers 3 and 4 provide means for steeringthe machine while the independently controlled drives for the conveyors5 and 6 and the spreader sections 1 and 8 provide means for varying theamount of material supplied at each side of the screed structure 2. Themotor 9 also drives a rearwardly extending shaft 3| at one side of theunit I which is provided for a purpose to be described later. All of theclutches are preferably controlled from a bank of controls 32 (Figures 2and 3) which is provided at one side of the machine or from a bank ofcontrols 33 which is provided at the other side of the machine. Anoperators seat 34 is preferably removably supported at the rear of theunit I so that it may be positioned adjacent either the controls 32 orthe controls 33 to obtain good visibility at either side of the machine.

As previously indicated, the screed structure 2 is disposed at the rearof the unit I and extends transversely thereof. The frame of the unit Iis provided with upwardly and rearwardly extending supporting arms 35 ateach side of the frame as shown in Figures 1, 3 and 4. Each of the arms35 carries a pulley 38 about which a cable 31 is passed. The lower endsof cables 31 are connected at 38 to the upper transverse beam 39 of theframe of the screed structure 2, as shown best in Figure 6. As shownbest in Figure 2, the opposite end of each of the cables 31 is connectedto a piston rod 49 of a hydraulic cylinder and piston unit 4I disposedat each side of the frame of the unit I a substantial distance forwardlyof the rear end thereof. These hydraulic cylinders 4I are provided withthe usual valve controls and it will be apparent that they may beactuated to quickly raise or lower the entire screed structure. Thiscable arrangement provides for supporting the screed structure from theunit I for transportation or for lowering it into operative position.

The screed structure 2 is connected to the unit I by drag links whichpermit the necessary relative vertical movement between the unit I andthe. screed structure 2. A lower drag link 42 is provided at each sideof the unit I, as shown best in Figures 1, 4 and 5, and is pivoted tothe frame thereof for vertical movement, as at 43. The rear end of thedrag link 42 is pivoted to the screed structure 2 by means of a pin 44carried by a pair of upstanding arms 45, as shown in Figure 6, whichform a part of the screed structure frame and are rigidly connected attheir upper ends to the beam 39. To prevent undue tilting of the screedstructure 2, an upper drag link 46 is provided at each side of the unitI with its forward end pivoted to the frame thereof, as at 41. The rearend of the link 48 is pivoted at 48 to the transverse beam 39 of thescreed structure frame adjacent the end thereof. Thus, the screedstructure 2 will be pulled along with the unit I by the lines 42 and 45and the unit I will be free to move vertically relative'to the unit 2without affecting such unit. This is advantageous since the unit I willoperate on the relatively rou-gh surface to be covered. Furthermore,vertical movement of the unit 2 relative to the unit I created byactuation of the hydraulic cylinders 4I will be permitted.

An additional cable and pulley arrangement is provided for yieldablysuspending the screed structure 2 in operative position to act on thematerial to be finished. This structure is shown best in Figures l, 3,4, 6 and 8. With reference to Figure 4, it will be noted that the upperpart of the frame of the unit I is extended slightly beyond the rearends of the arms 35 and supports a transverse beam 5U. As shown best inFigure 6, suspended from each end of this beam by a bracket 5I is apulley 52. Around each of these pulleys passes a cable 53. The upperends of these cables are directed inwardly towards each other and areconnected to an adjustable cushioning unit 54. The lower end of each ofthese cables is anchored to a drum 55 (Figures 6 and '1) carried by thebeam 39 of the screed structure 2 adjacent theend of such beam andhaving a ratchet 58 associated therewith.

The unit 54 is transversely, disposed beneath the beam 50 of unit I and,as shown in Figure 8, includes a housing composed of telescoping tubularsections 51 and 58, the section 51 threading into the section 58. Theouter end of the section 51 is connected to the end of the lefthandcable 53 (Figure 6) while the right-hand cable 53 is connected to theend of a rod 59 ausgew extending outwardly from the sectionk 58. TheIrod 59 isl slidably mounted in thev end of the section 58 and extendsinto the section 57 having a compression springV 60 surrounding` it; Atone end this spring bears against the head Vof section 58 and at itsother end it bears against a stop nut .8| provided on the` rod' 59. Thespring' 60 may be compressed to the desiredv extenty by threadingsection T into orfout of the section 58.

The drums 55 are rotatably carried by the ilanges of the beam 39 andimay be rotated. by

means of cranks applied'. to the ends 63| of the* supporting shaftsthereof. These' shafts 63 carry ratchet gears 84 (Figures 6 and '7)Vwhich are engaged by pawls 65 normally heldin engage'- ment therewith bysprings 66. the drums 55 are prevented from rotating. How'- ever, theymay be rotated when thek pawls 85 are released. Rotation of the drums55' rwill either' further compress the spring; |59V or permit it' toexpand, depending upon the direction ofY rotation of the drums. Eitherdrum may beA rotated independently. Thus', the resistance of the'Yspring 88 may be varied readily. The drumsshould be so adjusted that aportion of the weight of the screed structure 2 will be supported fromthe unit I by the cables 53. However, the screed structure shouldcontact the material with` suilcient weight to properly compress andfinish the surface thereof.

The screed structure itself is illustrated. best in Figures 6 to l1,inclusive. The frame of `this structure includes the transverse beam 39and the upstanding arms 45', previously mentioned. The lower ends of thearms 45 are welded. or otherwise suitably secured to the top surface ofa transversely extending inverted channel member 70` which extendsbeyond the outermost arms 45. Additional intermediate supports 45a mayalso be provided. This member 79 serves to adjustably support thesurfacing plate 7| of the screed structure. Ther plater 7| is flat andhorizontally disposed, as shown best in Figure 9, and is provided withan upstanding flange 72 at its rear edge. The forward edge has weldedthereto a bar 73 of square cross-section. Theplate 7| is secured toupstanding plates 74 and 75v disposed at its forward and rear edges andwhich are held in spaced relationship by sleeves 76 welded to the plates74v and 75. Bolts 77 are passed through the sleeves and through aligningopenings in the bar 73 and flange 72. It will be apparent that thesesleeves and bolt units will be provided at suitably spaced intervalsalong the plate 7|. Spaced above the sleeves 76- are sleeves 78 whichare also welded to the plates` 74 and 75. These sleeves receivetransversely extending clamping bolts 19 which pass through aligningopenings in the plates 74 and 75 and through vertical slots 80 in thedepending flanges 8| of the channel 78. The forward ends of the clampingbolts 79 also pass through aligning openings in a vertically disposedplate 82 adjacent the lower edge thereof. This plate is provided infront of theV forward flange 8| of channel 78 and extends upwardly abovethe top thereof having a rearwardly directed supporting flange 83.Welded to each of the sleeves 78 is the lower end of a thrust rod 84.Each of these upstanding rods 84 extends upwardly through an opening ina plate 85 and through an opening 89 in the top plate of the channel 78.It will be noted that the plate 85 is disposed above` the lower edges offlange 8| of channel `79 andis boltedthereto as at 87. Eachrod*extendsbeyoridy Thus,v` normally 8. the upper plate of channel 70through an opening 86a provided in an inverted channel 88 which extendstransversely of member 70 and is welded to the upper surface thereof. Inthe opening 87 a grooved collar 89 is disposed. The groove of thiscollar is engaged on opposite sides by the notched bars 90 which aretransversely disposed on opposite sides of the collar 89 and are securedto the channel 88 by bolts 9|. The arrangement of these bars isillustrated well in Figure 7. Above the collar 89 and formed as anintegral part thereof is a nut 92. The collar is threadedon the threadedupper end 93v of the rod 84. It will be apparent that the rods 84,arranged at intervals along the channel 79, serve to suspend thesurfacing plate 7| from the channel in suchl a manner that the surfacingplate 7| can be bowed to the proper crown desired to be imparted to thesurface of the material being finished.

In adjusting the crown, vit is merelyr necessary to apply a wrench tothe nuts 92 of collars 89V of the various thrust rod units, two of suchunits being shown in Figure '7 spaced inwardly from opposite ends of thechannel 78. Any desired number of these units, however, may be provided.Adjustment of the nuts 92 will exert a thrust or pull on the rods 84'which will transmitl such force to the sleeve 78 which will', in turn,transmit the force to the plates 74 and 75 and the plate 7|, the latterthree plates being joined together as a single unit. This last-mentionedunit will, therefore, be bowed to the proper crown. During thisadjustment the nuts 79a on the bolts 79 will be loosened to permit movefment of the plates 74 and 75 relative to the flanges 8|Y of channel 79and as soon as the adjustment is completed, the nuts will be tightenedto clamp these various members together. Vertical movement of plate 74will result in correspondingV movement of the plate 82. Thus, thesurfacing plate 7| can have the proper crown imparted thereto by asimple adjustment.

Directly in front of the surfacing plate 7| is the transverselyextending cutter bar 95 which is supported for transverse oscillationrelative to the stationary plate 7|. As shown in Figure 6, the cutterbar is composed of several sections to permit adjustment in accordancewith the crowning of the plate 7|, three sections being shown, that is,a middle section 96, a left-hand section 97, and a right-hand section98. Each section of the cutter bar is provided with a flat rear surface95a which bears against the forward surface of the bar 73 secured to theforward edge of plate 7|. The forward edge of each section is providedwith teeth or serrations 95h which are preferably disposed at an angleof approximately 45 relative to the flat plate 7|. In other words, theserrated edge of the cutter bar is directed rearwardly and downwardly atan angle of about 45. In order to permit oscillation of the cutter bar,its sections are suspended from the plates 82 by means of the pendulumlink units 99. As shown in Figure 6, one of these units is disposed atthe outer end of the cutter bar section 97, another at the adjacent endsof sections 97 and 96, another at the adjacent ends of the sections 98and 98, and another at the outer end of section 98. However, the numberof these units 99 will depend upon the number of sections of. the cutterbar, which can be varied.

t will be noted best from Figures 9 and 10 that each of the cutter barsections is provided with an upstanding forward flange |00 which isremovably bolted to a plate |0l, these platesbeing provided in the samenumber as the cutter bar sections and being substantially'of the samelengths. The cutter bar flanges are bolted to the plates I0! byremovable bolts |02 so that the cutter bar sections can be removed andreplaced when desired. As shown best in Figures 6, 7, 9 and 14, the endsof the plates |0| are provided with integral collars |03, the collarsbeing associated with the suspending link units 99. It will be notedfrom Figures 9 and 14 that at the adjacent ends of plates |0l, that is,at the junction of sections 95 and 91 and at the junction of sections 96and 98 of the cutter bar, the collars |03 are offset relative to eachother so that they can be supported by the same pivot |04 but-still theadjacent cutter bar sections will be in alignment with each, other,presenting a continuous serrated edge at the forward side of the screedfor engaging the material. The outer ends of sections 91 and 98 of thecutter bar are supported from the links 99 in the same manner as theinner ends thereof and the ends of sections 96 are supported, whichsupport is shown in Figures 9 and 14 in detail, except that only onecollar |03 will be provided at these pivot points |0411 (Figure 6).

With reference to Figures 9 and 14, it will be apparent that each collar|03 is provided with a bushing |05 keyed thereto by a key |06. Withinthe bushing |05 is a rubber sleeve |01 and within the sleeve |01 is abushing |08 keyed to the pivot pin |04 by means of a key |09. The rubbersleeve |01 is molded between the bushings |05 and |68 and adheresthereto so thatl it will not rotate relative thereto. The pin |04 isdisposed in openings formed in the supporting brackets ||0 and |I|disposed at opposite sides of the collars |03. The pin |04 is preventedfrom rotating in these brackets by means of set screws ||2 and ||3 andis prevented from axial movement by afnut I |4. The brackets ||0 and arebolted in clamping relationship by means of a plurality of bolts ||5 tothe lower end of a bar 6 which forms a part of each of the link units99. Tightening of the nuts I I5 and the nut I4 will cause the twoadjacent rubber sleeves |01 to frictionally engage each other and eachsleeve to engage the adjacent plate ||0 or The upper end of each bar lI6 has a collar l1 formed integral therewith. Within this collar is abushing ||8 which is keyed thereto by a key ||9. Within the bushing ||8is a rubber sleeve |20 and within the sleeve |20 is a bushing |2|,

the rubber sleeve being molded between and adhering to the two bushingsso as not to rotate relative thereto. .The bushing. |2| is keyed bya key|22 to a pin |23. The pin |23 is supported by a bracket |24 which isbolted by means of bolts |25 to the rearwardly extending ange 83 of thevertical plate 82. A- cover and clamping plate |26 is held on the outerend of the pin |23 by means of a nut |21. A flange |28 on theoppositeend of the pin |23 limits axial movement thereof to the right, as shownin Figure 9. Axial movement of bushing ||3 relative to collar |1 isprecluded by a screw |29. When nut |21 is tightened, the plate |26engages rubber sleeve |20 and causes it to also engage a spacer sleeve|30 provided behing the bushing structure in contact with the forwardside of bracket |24. It will be apparent that with this arrangement Ihave provided a yieldable pivot structureassociated with upper pin |23and a yieldable pivot structure associated with lower pin ||2. In eachcase, the pivot structure is not a free pivot structure, with relativelyrotatable metal parts which would require lubrication, but yieldssufficiently, due to the provision of the rubber sleeves |20 and |01.The parts do not rotate relatively but the material of the rubbersleeves will yield sufciently to permit the necessary limited movementabout the axes of the pins. Furthermore, no lubrication is required.

As previously indicated when the plate 1| is bowed, the vertical plate82 is moved vertically to a slight extent. In order to adjust the cutterbar sections relatively in accordance with the crown imparted to thesurfacing plate 1|, the supporting brackets |24 for the pendulum linkunits 99 can be adjusted vertically. This is accomplished by removingthe bolts |25, which bolt the brackets 24 to the flange 83, and varyingthe number of shims |3| provided between each bracket and the flange.This will raise or lower the pin |23 supported by the bracket |24 andthe associated link structure. It usually will only be necessary toadjust the two intermediate link units 99. This will change the angle ofsection 96 relative to sections 91 and 98, these sections having aslight space between their adjacent ends (Figure 14).

Oscillation of the cutter bar relative to the surfacing plate 1| isaccomplished by means of an eccentric drive |32 which is illustratedbest in Figures 3, 5, 6 and '1. This drive includes a pitman |33 whichis pivotally connected as at |34 to an upstanding bracket |35 bolted bybolts |36 to the center plate |0| of the cutter bar structure. Theopposite end of this pitman |33is provided with a collar |31 whichreceives the rotatable eccentric |38. This eccentric is keyed on a shaftwhich is rotatably mounted in a bearing sleeve |39 that is provided witha supporting base |40 bolted by bolts |4| to the upper surface of thechannel 10. The opposite end of the eccentric supporting shaft carries asprocket |42 which is driven by a chain |43. This chain |43, as shownbest in Figure 5, is driven by means of the shaft 3| which extendsrearwardly from the tractor unit The rear end of the shaft 3| isconnected by a universal connection to a short shaft section |44 whichis connected by a universal connection to a stub shaft |45 which isrotatably carried in a bearing |46 secured on the cross beam 59 at therear of the unit The rear end of this shaft |45 carries the sprocket |41which drivesthe chain |43. Thus, the eccentric drive |32 will be drivenfrom the power unit on the tractor unit by a iiexible connection whichwill permit verticalmovement of the screed structure 2 relative to theunit The eccentric drive is such that the cutter bar will be oscillatedat a very high speed relative to the surfacing plate.

Disposed directly ahead of the link units 99, which suspend the cutterbar, and the eccentric drive |32 is a vertically disposedmaterial-engag'ingV plate |48 which protects this mechanism. This plate|48v by forwardly extending thrust members |49 which are disposedbetween the plate |48 and the upstanding supports 45 and 45a or thescreed frame structure to which the members |49 may be welded orotherwise suitably secured. The plate |48 is connected to the members|49 by bolt and slot connections |50 so that the plate |48 is verticallyadjustable. This plate |48 may be formed in sections corresponding innumber and lengths to 'the cutter bar-section. The lower edge of theplate |48 is turned rearwardly and downwardly to provide an angularlydisposed portion |5| which is pref- 11 erably disposed at substantiallythe same angles as the teeth of the cutter bar. As the screed advancesinto the material, the plate |48 engages the material and its lower edge|5| directs the material downwardly beneath the cutter bar 95.

In order to prevent the material being acted on by the screed fromspreading laterally beyond the ends of the screed, I provide thevertically disposed side plates |52 at the ends vthereof which formstraight edges on the layer of material finished by my machine. As shownbest iin Figure 5, these plates extend rearwardly from a point ahead ofthe rotatable spreading member carried by unit to a point behind thesurfacing plate H .of the screed. The forward end of each plate ismounted for slidable vertical movement in a guide |53 carried by theframe of the unit I, as shown best in Figures 4 and 5. The rear end ofeach plate is similarly disposed in a guide |54 which is bolted to therear flange 8| of the channel 10 of the screed structure. These platesmerely slide along the surface and move or float vertically inaccordance with the irregularities thereof. Pins |55 are associated withthe forward and rear upper corners of each of the plates |52 to preventthe plates from dropping from the guides |53 and |54 whenever the screedstructure is raised for transportation.

I also provide a heating system for heating the surfacing plate 1| andthe cutter bar v95 so that it can operate satisfactorily on bituminousmaterial. This structure is shown best in Figures 12 and 13. The plate85 extends almost the full length of the channel 10 but one end isspaced slightly from the adjacent end thereof. The ends of the box-likescreed structure formed by members 1U, 1|, 14 and 15 may be closed byplates |58 which are bolted to the channel 1U.

Thus, upper and lower heat conducting passageways |51 and |53 areprovided within the screed structure, the one end of passageway |51communicating with the corresponding end of passageway |58, as shown inFigure 12. The passageway |58 has its bottom wall formed by the plate1|. Consequently, when heating medium is passed through the lowerpassageway |58 the heat is conducted into plate 1| and from this plateinto the contacting bar 13 and the cutter bar S which contacts with suchbar 13. Heat is supplied to the upper passageway |51 by means of .avertical .duct |59 which extends downwardly from a heating unit |60 andis connected to the passageway |51 through an opening provided `in thetop .of the channel 1.0 intermediate the ends thereof. This heating unit|60 is supported on the upper beam 39 of the screed frame intermediatethe ends thereof and may be of any suitable type preferably including .ablower |61. An escape `opening |62 for the heating fluid or .gas may beprovided behind a baille plate .|63 which is kprovided in the upperpassageway |51. Thus, with this arrangement the heating medium forcedinto the passageway |5 1 will travel therethrough and then downwardlyinto Ythe passageway |58, through this passageway and 'then out throughthe vent |62.

In the operation of this machine, rthe hydraulic cylinders 41 will beactuated to lower the screed structure 2 Vto operative position. Thescreed structure will be 'suspended in such position by the cablearrangement which includes the cushioning unit 5 1 in such a vmannerthat a proper amount of weight will be applied to the material beingactedupon. As the unit advances, it

will pull `the screed structure 2 along therewith, limited verticalmovement of the screed structure and Athe unit relatively beingpermitted by the drag link connecting structure including the links 42and 46. The material supplied in front of the screed structure by theunit will rst be engaged by the plate |48, the thrust of this materialbeing taken by thrust members |49 and the main frame of the screedstructure. The material will be directed rearwardly and downwardly asshown in Figure l1 by the lower angular portion |5| of the plate |48.The cutter bar 9 5 will be oscillating at high speed and will engage.and agitate the material being fed to it by portion |5| of plate |48.The thrust created on cutter bar will be transmitted to bar 13. Thisagitation will aid in the feeding of the material beneath the cutter bar95 which will gradually compress it and force it under the surfacingplate 1|, cutting it oi at the level of the surfacing plate 1|. Theplate 1| will then pass over .the compacted material and will smooth itand surface it to proper contour. The crown of .the plate 1| may bereadily adjusted as previously indicated and the sections of the cutterbar 95 may be adjusted correspondingly. rlShe ends of the cutter bar, asshown best in Figure 6, will be spaced from the side plates |52 topermit the required longitudinal movement of the cutter bar .duringoscillation thereof.

It will be apparent from the above description that the finishingmachine which I have developed has many advantages. The screed structurethereof is such that as it advances through the material, it willagitate it. compact it and direct vit under the moving surface of thescreed at the same time that it is cutting the material off to vthelevel of such smoothing surface. Because vthe cut-off bar is serrated.it more eectively agitates the material vand since the teeth aredisposed at an angle relative to the xed smoothing plate, the materialis gradually forced downwardly and rearwardly under such plate.Furthermore, since the surfacing plate and serrated cut-off bar areheated, the screed structure will act effectively on hot mix material.The oscillation of the cut-oir bar is accomplished without unduevibration of the main screed structure due to the special link structurewhich is provided for suspending the cutter bar and which includescushioning elements. The screed structure is suspended in an operativeposition by a cable structure which includes a cushioning unit that maybe adjusted to vary the amount of weight lapplied .to the material beingacted upon. This weight may be adjusted for various materials which isimportant in the case of slow-curing materials which should not becompacted to an excessive degree, which might occur if all of the weightof the screed structure was applied to the material. Furthermore, thescreed structure may be raised quickly into operative position fortransportation by the tractor unit through the medium of the hydrauliccylinders and cable ar rangement which I provide for this purpose.

Various other advantages will be apparent from the precedingdescription, the drawings and the following claims.

Having thus described my invention, what I claim is:

. 1. A finishing machine comprising a vehicle adapted to move along thesurface to be finished, a screed structure adapted to act upon thematerial to be Vinished, means for suspending the screed structure fromthe vehicle, said means comprising a pair of cables having one of theirends connected to said screed structure and their opposite Aends passingaround guides carried by the vehicle and being connected to the oppositeends of a plunger unit, said unit including a rod connected to one ofsaid cables and a housing connected to the other of said cables, and acompression spring disposed in said housing for resisting movement ofthe rod relative thereto in the direction -which the weight of thescreed structure tends to pull it.

2. Apparatus according to claim 1 wherein the housing is formed oftelescoping sections of cylinders which have intertting threaded ends.

3. Apparatus according to claim 1 wherein the ends of the cables areanchored to drums carried by said screed structure, and releasable meansfor normally preventing rotation of said drums but permitting rotationwhen desired to vary the extent of compression of said spring in saidhousing.

4. Apparatus according to claim 3 wherein said last-named meanscomprises releasable ratchets associated with said drums.

5. Apparatus according torclaim 3 including a second cable arrangementfor supporting the screed structure completely from the vehicle or forlowering it so it will be suspended by the firstnamed cable arrangement,said second cable arrangement comprising a pair of cables having one oftheir ends anchored to said screed structure and their opposite endspassing around pulleys supported by the vehicle and being connected tohydraulic cylinder units carried by said vehicle.

6. A screed structure comprising a transversely xed surfacing member forimparting a smooth surface to the material being acted upon, a cutterbar disposed at the forward edge of said surfacing member, means foroscillating said cutter bar transversely relative to said surfacingmember, said cutter bar having a serrated materialengaging face which isdirected downwardly and rearwardly to a point substantially level Iwiththe lower surface and contiguous with the forward edge of said surfacingmember, and a vertically disposed material-engaging plate"` in front ofsaid cutter bar, said plate having its lower edge inclined downwardlyand rearwardly so that it is substantially continuous with said face ofsaid cutter bar and will direct the material thereto as the screedstructure is forced into the material.

7. A screed structure according to claim 6 wherein the serrated face ofthe cutter bar is disposed at an angle of approximately 45 relative tothe lower surface of the surfacing member and the inclined lower edge ofsaid vertically disposed plate is arranged at a corresponding angle.

8. A screed structure comprising a supporting frame, a surfacing platesupported at the lower side of said frame in transversely fixed positionfor imparting a smooth surface to the material being acted upon, acutter bar supported from said frame for horizontal oscillationtransversely of the frame at the forward edge of said plate, meanscarried by said frame for oscillating said cutter bar, said cutter barhaving a serrated material-engaging face which is directed downwardlyand rearwardly to a point substantially level with the lower surface andcontiguous with the forward edge of said surfacing plate, and amaterial-engaging plate in front of said cutter bar, said plate havingits lower edge inclined downwardly and rearwardly so that it issubstantially contiguous with said face of said cutter bar and 14 willdirect the material thereto as the screed structure is forced intothe'material.

9. A screed structure according to claim 8 wherein the face of thecutter bar and the inclined lower edge of said front plate are disposedat an angle of approximately 45 from the horizontal.

10. A screed structure comprising a supporting frame, a surfacing platesupported at the lower side of said frame in transversely xed positionfor imparting a smooth surface to the material being acted upon, acutter bar supported from said frame for horizontal oscillationtransversely of the frame at the forward edge of said plate, meanscarried by the frame for oscillating said cutter bar, said cutter barhaving a serrated material-engaging face which is directed downwardlyand rearwardly to a point substantially level with the lower surface andcontiguous with the forward edge of said surfacing plate, said cutterbar being suspended from the frame by pendulum links which are pivotedto the frame and to the cutter bar, the pivot points of said linksincluding bearings embodying yieldable sleeves which permit oscillationof said links.

11. A screed structure according to claim 10 wherein the cutter bar iscomposed of several sections, some of said sections having theiradjacent ends at the points where certain of said links are pivoted tosaid bar, and an adjustable support carrying said links and beingsupported on said frame for vertical adjustment to permit angularrelative adjustment of said adjacent cutter bar sections.

12. A screed structure comprising a supporting frame, a surfacing platesupported at the lower side of said frame in transversely fixed positionfor imparting a smooth surface to the material being acted upon, acutter bar supported from said frame for horizontal oscillationtransversely of the frame at the forward edge of said plate, meanscarried by said frame for oscillating said cutter bar, said cutter barhaving a serrated material-engaging face which is directed downwardlyand rearwardly to a point substantially level with the lower surface andcontiguous with the forward edge of said surfacing plate, saidoscillating means includes an eccentric rotatably supported on saidframe, a vehicle for carrying said screed structure, means for mountingthe screed on the vehicle for vertical movement relative to the vehicle,a power unit on said vehicle, and a flexible driving connection betweensaid power unit and said eccentric to permit such vertical movement.

13. A screed structure including a supporting frame, a material-engagingmember supported by said framameans for suspending said member from saidframe and including links, a bearing provided at one end of each of saidlinks, said bearing including a pair of axially spaced sleeves with aflexible sleeve interposed therebetween which will flex sumciently topermit oscillation of said link, and means for oscillating saidsuspended member.

14.. A structure according to claim 13 wherein the bearing includes twometal sleeves with a rubber sleeve interposed therebetween and beingnon-rotatable relative to said sleeves.

15. A structure according to claim 14 wherein one of said bearings isprovided for connecting one end of each link to the said frame and oneof said bearings is provided for connecting the other end of each linkto said material-engaging member.

HAROLDYR. HORNING.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date Gardiner Jan. 8, 1935 Number 16Name Date Mosel Apr. l21,1936 -Owens et a1. Aug. 16, 1938 Blackwell Mar.14, 1939 Mosel Jan. 2, 1940 Heltzel Dec. 24, 1940 Heltzel Mar. 18, 1941Heltzel June 3, 1941 Jackson Nov. 4. 1941 Heltzel Mar. 2, 1943 Mandt etal. June 21, 1949

